Automatic grinding attachment for bottom roughing machine



DeC. 29, 1970 w, BOQT ETAL 3,550,329

AUTOMATIC GRINDING ATTACHMENT FOR BOTTOM ROUGHING MACHINE Filed Dec. 12, 1967 5 Sheets-Sheet l Dec. 29, 1970 w, BOOT ETAL V 3,550,329

AUTOMATIC GRINDING ATTACHMENT FOR BOTTOM ROUGHING MACHINE Filed Dec. 12, 1967 3 Sheets-Sheet 2 I H J24: 5 1111mm i i 66 133 I Q [14 70 //2\ W0 Dec. 29, 1970 H. w. BOOT ETAL 3,550,329

AUTOMATIC GRINDING ATTACHMENT FOR BOTTOM ROUGHING MACHlNE Filed Dec. 12, 1967 C5 Sheets-Sheet 3 United States Patent 3,550,329 AUTOMATIC GRINDING ATTACHMENT FOR BOTTOM ROUGHING MACHINE Herbert W. Boot and Frederick H. Langton, Leicester, England, assignors to USM Corporation, Flemington, N .J., a corporation of New Jersey Filed Dec. 12, 1967, Ser. No. 689,989 Claims priority, application Great Britain, Jan. 28, 1967,

67 Int. Cl. B241) 19/00, 49/00, 51/00 US. Cl. 51-241 12 Claims ABSTRACT OF THE DISCLOSURE There is disclosed an automatic resurfacing device for removing a predetermined amount of exterior material from a rotary abrasive tool. The device includes as an integral part, means for returning the abrasive surface of a brush to a prior datum plane following the resurfacing, relieving the operator of the need to readjust the machine.

BACKGROUND OF THE INVENTION This invention relates to improvements in apparatus suitable for use in operating on shoes. In particular, the invention relates to apparatus for use in performing a roughing operation on marginal portions of a shoe bottom. It is to be understood that the term shoe where used herein is intended in the generic sense including footwear generally as well as an article of footwear during the course of its manufacture.

There is described in US. Pat. 3,233,438 granted to Hansen et al. apparatus for performing a roughing operation on the marginal portions of shoe bottoms. In general, the machine described in the above noted patent comprises a frame and a shoe support for supporting a lasted shoe bottom uppermost. The shoe support is mounted for sliding movement on the frame. A pair of rotary roughing tools such as stiff bristled brushes are supported on two generally horizontal arms mounted for pivotal movement about both horizontal and vertical axes. The two tools are automatically guided during the roughing operation by means of a template and progressively operate along opposite marginal portions of the shoe bottom as it is moved beneath the tools. The tools are placed with the abrasive surface in a datum plane assuring contact with the entire shoe bottom.

In use, it has been found necessary to frequently regrind the brushes in the above noted machine to sharpen the bristles and assure fidelity to the template. The frequency of resurfacing the brushes by sharpening the bristles depends upon the material from which the shoe is made. Customarily, regrinding of the brush is performed by rotating the brush and manually presenting a grinding stone thereto. Apart from possible difficulty of access to the brushes for manual resurfacing, there is no way in which the amount of bristle removed during the grinding can be regulated. The above described machine has wire brushes that are arranged so that their work engaging surfaces are disposed on the horizontal datum plane to which the heightwise position of the lowermost portion of a shoe is located. It is important that the brushes be accurately repositioned in correct relation to the datum plane after each sharpening operation to assure a uniform finished product.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a mechanism for automatically resurfacing an abrasive tool and for returning the working surface of the tool to a previously determined datum plane.

Patented Dec. 29, 1970 It is another object of this invention to provide an automatic resurfacing device for use with abrasive brushes and which accurately control the amount of material removed from the brush.

Yet another object of this invention is to provide a mechanism which will resurface abrasive tools at predetermined variable intervals assuring a uniform abrasive quality.

In accordance with these objects and as a feature of this invention, there is provided a shoe bottom roughing machine incorporating an automatic means for periodically resurfacing the rotary roughing brushes. The rotary brush resurfacing means includes, as an integral part thereof, means for accurately controlling the amount of material removed from the brush and for repositioning the brush, adjusting the axis to accommodate for this removal. The use of the means automatically assures the return of the working surface of the brush to the required datum plane removing this critical placement from the possibility of human error.

The illustrative resurfacing means further includes a control mechanism which is set by the operator prior to the beginning of a production run. The control mechanism is adjusted to resurface the rotary brushes after a predetermined number of operating cycles, the number of cycles between resurfacing depending upon the material roughed by the tool.

The above and other features of the invention including various novel details of construction and combinations of parts will now be more particularly described with reference to the accompanying drawings and pointed out in the claims.

It will be understood that the particular machine embodying the invention is shown by way of illustration only and not as a limitation of the invention. The principles and features of this invention may be employed in varied and numerous embodiments without departing from the scope of the invention, for example, are applicable to any type of rotary tool grinding or sharpening mechamsm.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in side elevation of an illustrative shoe bottom roughing machine embodying the invention;

FIG. 2 is a fragmentary view with portions broken away showing the arm height adjusting mechanism means of the illustrative apparatus;

FIG. 3 is a section view taken along lines IIII'II of FIG. 2; and

FIG. 4 is a fragmentary view of that portion suspended beneath the frame broken away and blown up showing the control means of the illustrative apparatus.

FIG. 1 shows a shoe finishing machine into which the invention has been incorporated. The machine as shown is essentially the same as that disclosed in US. Pat. 3,233,- 438 noted above and basically comprises: a frame 2, a slidably mounted shoe support 4 upon which a lasted shoe upper 6 is rigidly clamped by clamping means 8 and 10, and mounted generally above the movable shoe support, a pair of forwardly extending arms 12 and 14 upon which are mounted at the outer end a pair of abrasive brushes 16, 18. Mounted immediately above the rotary brushes 16, 18 are a pair of dust hoods 20, 22 connected to a vacuum conduit 24. Mounted upon the upper surface of shoe support 4 are a pair of grinding stones 26, 28 mounted upon bases 27, 29 respectively, which underlie the abrasive brushes 18, 16 when the shoe support is in its rearwardmost position i.e. to the right of FIG. 1. It is to be noted that although the grinding stones 26, 28 as well as the abrasive brushes 16, 18 are shown with curved corresponding surfaces, all that is necessary is that they have complementary shapes. Mounted upon the upper portion of each of the arms 12, 14 is an arm height adjusting mechanism including an extension 34 which terminates beneath the arm 12 and rests upon the top of a piston rod 36 reciprocally mounted in cylinder 38. Depending from the lowermost portion of frame 2 can be seen a control means 40 which will be described in greater detail later.

ARM HEIGHT ADJUSTMENT The height adjustment mechanism is identical on each of the arms and so only one will be described in detail.

As can be seen in FIGS. 2 and 3, the arm height adjustment 30 of FIG. 1 is mounted upon the abrasive wheel carrying arm 12 and comprises a base plate 50, a housing 52, a cover plate 54 and a pneumatic cylinder 56. Rigidly mounted on the upper portion of the cover plate 54 is a lug 58 which has pivotally mounted thereon a bell crank 60, one arm of which extends through the cover plate 54 and carries a stud 62 which fits into a slot 64 in a three-armed lever 66 (see FIG. 3). The other arm of the bell crank is received between two spaced flanges 68 on a shaft 70 which extends downwardly through the cover plate 54, through a bearing 72 mounted in the base plate 50 and into a bore of square cross section 74, formed in a block 34 which is secured to the underside of the base plate 50. The lower end portion of the shaft 70 is threaded and has screwed thereon a block 78 of square cross section which is slidable mounted in the square bore 74 of block 34 and projects below the lower extreme of the block 34. The lower end of block 78 rests upon an enlarged head portion 37 of the piston rod 36 thus supporting the arm 12.

Rigidly mounted on the base plate 50 is an upstanding shaft upon which the three-armed lever 66 is pivotally mounted. As is described above, one arm of the three-armed lever 66 has a slot 64 (FIG. 3) which receives the stud at the lower end of the bell crank 60. Another arm of the three-armed lever 66 is pivotally secured to a clevis 92 which is, in turn, attached to a piston rod 94 extending from the cylinder 56. Mounted upon the third arm of the three-armed lever 66 is a pawl 96 designed to interact with the rachet wheel 98 rigidly mounted upon shaft 90 and which pawl is spring biased towards the center. of the rachet wheel 98, assuring positive engagement between the pawl 96, and the rachet wheel 98. Also fixed upon shaft 90 is a pinion which intermeshes with a pair of larger gears 112, 114 of a continuous train. The largest gear 114 is rigidly attached to the shaft 70 and the pinion 110 is rigidly attached to the rachet wheel 98.

Mounted adjacent the pawl 96 is a shaft extending between the base plate 50 and passing through the cover plate 54 terminating with a handle 122. Eccentrically mounted upon the shaft 122 is a cylinder 124 which has its rotation restricted by a pin 126 which is fixed to the base plate 50 and extends upwardly to halt the movement of the cylinder 124.

In operation, air under pressure is introduced into the cylinder 56 causing the piston rod to move toward a stop screw 130 mounted in the housing 52. The movement of the piston rod 94 causes the three-armed lever 66 to pivot about the shaft 90 in a clockwise direction (as viewed in FIG. 3). This movement causes the bell crank lever 60 to pivot in a clockwise direction (as viewed in FIG. 2) lifting the shaft 70 and the block 78 relative to the block 34 and the arm 12 thus causing the arm to be lowered. The abrasive tool, i.e. the wire brush 16 or 18, is thus caused to be moved towards the grinding stone 28 which is mounted directly beneath the tool when the shoe support is in its rest position. A spring 132 is supported upon a flanged portion 133 of the shaft 70 within the housing 52 and acts to urge the shaft 70 downwardly relative to the block 34. When the air pressure is exhausted from the cylinder 56, the block 34, the threearmed lever 66, the bell crank lever 60 and the shaft 70 4 are all returned to their initial position, the spring 132, urging the shaft 70 downwardly. Since the heightwise position of the shaft 70 is fixed by engagement with the bell crank levers60, the pivotal action of the bell crank lever 60 causes the block 78 to be raised relative to the block 34 and thus causes the arm 12 to be lowered still further and the brush supported thereby to be lowered towards its respective grinding stone. When the lever 66 returns to its initial position, the pawl 96 rides over the teeth of the ratchet wheel 98 so that no return movement of the shaft 70 relative to the block 78 takes place.

Thus, in the grinding operation of the illustrative apparatus upon admission of air to the cylinder 56, the block 78 is raised relative to the arm 12 by the simultaneous operation of the bell crank lever 60, the ratchet wheel 98 and thepawl 96 whereby the brush 18 carried by the arm 12 is lowered from its datum plane through a predetermined distance, determined by the bell crank lever, toward the grinding stone 28 and also through a small increment, determined by the ratchet wheel and pawl, which determines the amount of material to be removed from the brush. The brush is ground to the datum of the grinding stone and thereafter, through the bell crank lever, is returned to the prior datum plane.

For initially setting up the illustrative apparatus, each brush or other roughing tool can be placed in its proper datum plane by manually rotating shaft 70 and lowering the block 78 relative thereto. For this purpose there is provided on the upper end of shaft 90 a knob 134 by means of which shaft 90 and thus shaft 70 can be r0- tated. In order to prevent the pawl 96 from locking the rachet wheel against rotation there is provided an eccentrically mounted cylinder 24 rigidly connected to the knob 122. Rotation of the knob 122 will move the eccentrically mounted cylinder against the rear portion of the pawl 96 disengaging the pawl from the teeth of the ratchet wheel 98. It is to be noted that upstanding pin 126 limits the rotation of the eccentric cylinder to that direction in which it will cam against the rear portion of pawl 96.

CONTROL MEANS The illustrative apparatus also comprises control means 40 (FIG. 4) for instituting operation of the actuating means described above. The control means comprises a support plate mounted on the frame 2 of the apparatus and supporting a control disc 152 for rotation thereon. The illustrative control disc 152 is provided with twelve apertures 154 equally spaced in a circle concentric with the center of the disc and twenty-four teeth 156 equally spaced about the periphery of the disc. Each aperture 154 is capable of receiving a pin 158 in such a manner that as the disc is caused to rotate the pin will engage With a roll 160 mounted upon the outer end of a leaf spring 162 which urges the roll toward the center of the disc. The roll and spring combination are mounted so that when the roll 160 is contacted by a pin 158 the spring is forced away from the center of the control disc 150 and depresses a plunger of a micro-switch 164 mounted upon the support plate 150 adjacent the disc. By varying the spacing of pins 158 in the apertures 154 the micro-switch 164 can be operated at different in tervals in the operation of the illustrative apparatus. A further number of apertures 166 are provided in the disc for storing pins not in use.

Also mounted on the support plate 150 is a pneumatic cylinder 170 which has a block 172 affixed to the outer end of its piston rod. An adjustable stop screw 174 is provided on the support plate to limit the movement of the piston rod on admission of air to the cylinder. Pivotally mounted on block 172 and urged by a spring into engagement with a periphery of a control disc 152 is a pusher member 176 which engages with the teeth 156 of the disc and causes the disc to be rotated upon admission of air to the cylinder. When the pusher member 176 is retracted it rides over the teeth 172 against the action of the spring. Rotation of the disc in the opposite direction is prevented by a strip 178 mounted to the support plate In the operation of the illustrative device air is admitted to the cylinder 170 each time the shoe support 4 reaches the rearmost extent of its movement. The disc 152 is rotated through the distance between two adjacent teeth in each cycle of the operation of the apparatus. When the pins are disposed as shown in FIG. 4, i.e., in every fourth aperture, the control means will be operated in every eighth cycle of operation of the apparatus by one of the pins tripping the micro-switch 164. Operation of the micro-switch is effective to break a first electric circuit to a motor (not shown) and to initiate a timing release (also not shown) to cause the brushes to rotate in the opposite direction. The timing being such that the reverse drive is imparted to the brush as the shoe support reaches its rest position.

The completion of the circuit is also effective to bring the actuating means 30 into operation whereby the brushes are lowered into engagement with the grinding stones and the brushes are thus ground. Since the direction of rotation is reversed during the grinding operation, burrs formed on the ends of the bristles provide a cutting edge when rubbed against the shoe bottom.

A second timing relay, not shown, is incorporated and after a pre-set interval, the previously completed circuit is broken by this second relay and the brushes are again raised to the original datum plane and the reverse drive is discontinued. A third timing relay causes the brushes to again rotate in the original direction and a further cycle of operation of the apparatus can be performed.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent of the United States is:

1. A resurfacing device for use with a machine including a frame and at least one rotatable abrasive wheel including a working surface carried on a pivotable shaft mounted on the machine frame, the resurfacing device comprising a resurfacing tool mounted on the frame normally below and spaced from the abrasive wheel, means connected to the pivotable shaft to control the heightwise position of the pivotable shaft and the abrasive wheel further designed to be actuated at predetermined intervals by control means to periodically lower the abrasive wheel to the resurfacing means and to return the said wheel following resurfacing of the working surface to a position whereat the working surfare lies in the same plane occupied before resurfacing, the means for lowering the shaft comprising a first means for lowering the abrasive wheel to contact the working surface with the resurfacing means and a second means to control the amount of material removed from the wheel by resurfacing and to return the working surface to a prior datum plane, the said second means comprising a threaded shaft to support the pivotable shaft advanceable by small increments during each resurfacing to lower the abrasive Wheel the amount desired to be removed from the working surface and a ratchet and pawl combination included in said second means to prevent inadvertent changes in the location of the working surface.

2. A device as in claim 1 including means for reversing the rotation of the wheel during the resurfacing.

3. A device as in claim 1 including manual means for resetting the working surface of the abrasive wheel to the datum plane.

4. A device as in claim 1 wherein the control means comprises a control disc which is actuated during each cycle of the machine and by axially extending but removable pins actuates the resurfacing device only upon the completion of a pre-set number of cycles.

5. A device as in claim 1 wherein the first means comprises a reciprocal support member for the shaft which within predetermined limits regulates the lowermost position the shaft can occupy.

6. A resurfacing device for use with a machine including a frame and at least one rotatable abrasive wheel including a working surface carried on a pivotable shaft mounted on a machine frame, the resurfacing device comprising a resurfacing tool mounted on the frame normally below and spaced from the abrasive wheel, means connected to the pivotable shaft to control the heightwise position of the pivotable shaft and the respective wheel further designed to be activated at predetermined intervals by control means to periodically lower the abrasive wheel to the resurfacing means and to return the wheel following the resurfacing to a position whereat the working surface of the abrasive wheel lies in the same plane 00- cupied before the resurfacing, the said control comprising a control disc which is activated during each cycle of the machine and by axially extending but removable pins actuates the resurfacing device only upon the completion of a pre-set number of cycles.

7. A device as in claim 6 wherein the means for lowering the shaft comprises a first means for lowering the abrasive wheel to contact the resurfacing means and a second means to control the amount of material removed from the wheel and to return the working surface to the prior datum plane.

8. A device as in claim 7 wherein the first means comprises a reciprocable support member for the shaft which within predetermined limits regulates the lowermost position the shaft can occupy.

9. A device as in claim 7 wherein the second means com-prises a threaded shaft to support the shaft and is advanced by small increments during each resurfacing lowering the abrasive wheel the amount desired to be removed from the outer surface.

10. A device as in claim 9 wherein the second means includes a rachet and pawl combination to prevent inadvertent changes in the location of the working surface.

11. A device as in claim 6 including means for reversing the rotation of the abrasive wheel during the resurfacing.

12. A device as in claim 6 including manual means for resetting the working surface of the abrasive wheel to the datum plane.

References Cited UNITED STATES PATENTS 3,233,438 2/1966 Hansen et al 696.5 3,009,294 11/1961 Linden et al. 5-134.5X 2,713,234 7/1955 Hill -11.1OST

JAMES L. JONES, JR., Primary Examiner US. Cl. X.R. 

